RECORD: Darwin, C. R. Emma & George Darwin. 1873.08.22-28. Mimosa [Application of water]. CUL-DAR209.2.45-47. (John van Wyhe ed., 2002-. The Complete Work of Charles Darwin Online, http://darwin-online.org.uk/)
REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 5.2023. RN1
NOTE: See record in the Darwin Online manuscript catalogue, enter its Identifier here. Reproduced with permission of the Syndics of Cambridge University Library and William Huxley Darwin. The volume CUL-DAR209.2 contains materials on circumnutation of leaves and stems for Darwin's book Movement in plants (1880).
[45]
Down 1873
Aug. 22' 8º. 20' A.m. put in rather old small mimosa Mimosa leaf into pure water at 63º.
Did not open by 11.15 20 A.M. Warmed it up to 80º rather quickly. They did not op & did not open.
Aug 23rd They did not open. Taken out 9 Am. They were from 75º to 76º all night.
One leaf had been sunk by lead & the leaflets were so pressed together that they were to a great extent not wetted; one had been floating on the surface of the water, and in this case, they were dryer than in the other case. In both case the outsides of the leaves were very wet, towards their extremities
Mimosa
[46]
Down Aug 23rd 1873
A mimosa leaf was put into water at 64º whilst growing at 9º 10' A.M. It was completely covered by water; but some some of leaflets got partly out of water.
The leaflets generally opened partially & the water at about 11º was slowly heated at 101º some of the leaflets, at base of one of the pinnules, the tip being immersed in water, spontaneously closed.
Those that were quite immersed began, I believe, at about 90º insensibly to approach each other, & continued to do so till the water was heated to 130 1/2, but never quite closed.
2 Two leaflets at base of that pinnule, of which tip was immersed, & which did not close, spontaneously, closed when glands were touched.
The Aug 25th 9º The immersed leaflets have remained in the same state to the present time, ie almost closed, but not quite. I have now removed them out of water, (marked with yellow wool) & put in green house — The leaflets have a shrunk look & seem injured, & look yellowish or slightly discoloured. — Died & all dropped off. The leaflet of above leaf, of which tip had been immersed, are now still sensitive though only to slight degree.— (12º in greenhouse I can now see that leaves are dry that they are killed.)
(over)
[46v]
Aug 25th I have been deliberately trying, & find that the minute drops of water like a cloud for G. & F. refrigeration do not cause motion, in Mimosa except when accidentally a larger drop gets blown, but flicking minute drops from a few inches height from dust-brush, partly dry, is quite sufficient; so that we have here a limit — Blowing also causes movement—
Does sudden & complete darkness.?
Mimosa
[47]
Down
Mimosa Aug 27th. 1873
Mimosa leaf put in cold 1oz water at 2º.15' PM.
Began to be warmed 2º.52' temp 65º
3.2 temp 75º
3.35 82º leaf in water not opened
6. 35 90º.
opened 10. 15 PM 87º
Aug 28th 8. 35 AM 86º
12 91º
30 PM 92º
Taken ought 3.20 15/16 oz of water was in vessel. Put it in biggest evaporating dish 13/16 oz of the water that was in the vessel. No acid.
By comparing it with with pure water I perceived a slight colour. The water had a decided taste
The leaf kept shut in the water all the time.
The residue of 13/15th of the water was evaporated & left a thin crust which was scraped together & approximately all scraped together, but not with extreme care. The matter consisted of rather tenacious reddish brown substance, having a somewhat resinous appearance & weighed & therefore whole fluid must have contained a little more than rather above 3/100 a of a grain. When placed on heated platinum foil melted, swelled up largely & became vesicular & quite black— once I thought I perceived a slight animal odour, like from a bristle brush, but I am not at all of this. →
[47v]
Therefore a plant with 30 leaves wd lose about a grain of the organic matter in 24º if both sides of leaves were thoroughly thoroughly wetted & the temp. varied between 80º & 90º degrees.
{But wd not any Tropical plant thus treated lose matter???
Mimosa
Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)
File last updated 24 July, 2023